Stop valves are commonly found in in-line application in the water supply lines to sinks and toilets, water appliances which are normally supplied with water. The valves are usually found under the sink or toilet basin and serve as a convenient manual "shut off". Accordingly, the stop valve is normally always in the open position, permitting water to flow through the plumbing to the sink faucets and/or toilet basin valve; and are closed only on those infrequent occasions when repairs are to be made to the water appliance. Although several designs for this type of valve are offered in the trade, the most common stop valve construction incorporates O-rings and/or washers to form a seal and, moreover, consists of as many as eight separate pieces. Though the design is tried and true, the use of so many component parts has obvious cost implications for the manufacturer and ultimately for the customer. Other stop valves of more recent design are formed of a fewer number of parts to reduce cost, as few as three pieces per assembly. These incorporate a thin rubber tubular member that contains a hole in a cylindrical side wall that is rotated to align or mis-align the opening with a water passage to thereby open or close the valve. It is designed so that when in the closed position water pressure from the main supply lines enters the hollow of the tubular member forcing the member to radially expand and create a tighter seal. Such recent stop valves are easy to activate and require as little as a quarter turn, 90 degrees, to operate from a fully open to a fully closed position. U.S. Pat. No. 4,562,994 granted Jan. 7, 1986 to MacDonald and U.S. Pat. No. 4,609,177 Sept. 2, 1986 to Turner et al illustrate this kind of valve. Unfortunately it has been learned that some numbers of such valves have been found to leak even when newly installed. While satisfying criteria for minimal component element usage and cost, those three piece type valves do not engender the degree of comfort expected by the trade from the standpoint of function, which translates simply as; no water leakage permitted.
An object of the present invention is therefore to provide an effective stop valve containing a fewer number of component elements than the common design; to produce a stop valve that is of more economical construction and, when new, does not leak. It is a further object of the invention to provide a stop valve construction that does not use O-rings or washers as seals and which allows opening and or closing in as little as a quarter turn of the handle.